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As the land transport task, especially road is expected to increase significantly, by 2015, it would hardly be surprising that many policy makers will look to some form of urban transport environmental control long before this date. One method is via the introduction of a set of operational environmental hurdles. This is not a new concept. However, this paper proposes a new environmental initiative for urban transport operations. The scheme which is simple for both operators and regulators proposes an effective and meaningful operational rating system which reflects the efforts an operator may go to in their internal fleet environmental policies in purchasing equipment, daily workload planning, waste disposals policies etc.

The three tiered environmental operator performance rating scheme, the E-plus scheme has three levels of operator segmentation. A good basic auditable level of environmental compliance, an E rating, an excellent rating E plus, and an exceptional rating would be an E double plus. Probably no fleets currently in Australia would earn a double plus rating at this time.

Why should there be a road transport operator environmental rating scheme? Firstly as a measurable benchmark for the community and the fleet operators themselves. Secondly and a factor of growing importance is for the customers who are the buyers of freight services. Already customers are specifying in their tender requirements that transport operator environmental competencies and capabilities be listed. This may aid the selection of an operator for a specific task. For example; food sensitive freight handling may require specific food certification scheme adoption such as the HACCP classification system. Similarly an urban courier contract may specify, environmental credentials which sit under an ISO 14000 framework. However, what more specific operator differentiation criteria can be requested by the customer? The E plus system is being designed for this very purpose. In Australia some regulators and teaching centres have begun to take an interest in this transport operator framework.

The vehicle–track interaction and the resulting dynamic response of the vehicle involve a number of complex nonlinear problems. Large vertical loads act through a small contact patch leading to very high contact pressures. Transverse loads acting through this contact induce a relative velocity between wheel and rail expressed in non-dimensional form as a creepage. The wheel and rail profiles determine the contact patch shape and affect the ability of the vehicle to run stably. If the yaw stiffness of the axles is too low, the vehicle will become unstable at a relatively low speed; conversely, if the yaw stiffness is too high, the curving behaviour will be adversely affected. The vehicle suspension, especially the secondary suspension, also affects the ride comfort of passengers. Finally, it is shown how the speed profiles of accelerating and decelerating trains can be calculated from basic assumptions about the train power, adhesion and rolling resistance.